Mosquitoes

Mosquitoes - Fight the bight!

What are mosquitoes?

Mosquitoes are small, bloodsucking insects that belong to the family of flies called Culicidae. There are more than 300 different species in Australia however only 32 species in all commonly occur in South Australia.

Mosquitoes have a relatively short but complex life cycle consisting of eggs, four larval stages that develop in the water, a pupal stage in the water and an adult stage on land. The larvae cannot develop to the adult phase without access to water, and cannot develop in damp mud, soil or vegetation.

An adult female mosquito lays her eggs either on the water surface (usually as a floating raft) or on a surface that is often flooded with water (usually singly or in small groups). These egg-laying sites may include soil or vegetation at the edge of a wetland, soil or leaf litter where temporary pools form after rainfall, or in the inside of water –holding containers (e.g. tins, tyres).

Most adult mosquitoes are more active from dusk until dawn and usually seek refuge during the day in cool and humid sheltered habitats, such as in vegetation or under houses. Many mosquitoes do not travel far from their aquatic larval habitats, but some species can fly 5km or more.

On average, females live for approximately 2-3 weeks, males slightly less. Within their lifetime, adult male and female mosquitos will feed on nectar and other plant sugars, but only the female will seek a blood meal. The blood meal provides protein for egg development and, while many mosquitos are generalist feeders, some must specifically feed on humans, mammals, birds or amphibians.

Mosquito bites can be more than just a nuisance as some can also transmit diseases. The most common disease passed on by mosquitoes in South Australia is Ross River virus. Other serious infections transmitted by mosquitoes include viral encephalitis, Barmah Forest virus infection, dengue fever (in Northern Queensland and in tropical countries around the world) and malaria (in tropical countries around the world).

People can contract Ross River virus or Barmah Forest virus from certain species of infected mosquitoes in South Australia throughout the year, although most infections occur in the warmer months.

Following this simple advice will reduce the chance of mosquito bites and reduce the number of mosquitoes in the immediate environment.

Self protection from mosquito bites is the key to prevention.

Personal protection

Cover up with long, loose fitting clothing of sufficient thickness to prevent mosquitoes biting through the fabric.

Avoid exposure outdoors when mosquitoes are most active.

Use an insect repellent containing DEET or Picaridin (the most effective repellents contain 5-20% di-ethyl-N-toluamide or DEET) on exposed skin. Apply in accordance with the manufacturer’s instructions. Avoid using on babies and toddlers.

Use flyscreens and mosquito nets in accommodation where there are no flyscreens, especially for babies. (This is particularly important when camping out, as repellents are only effective for around four hours.)